Topological Similarity-Based Scheme for Large-Scale Group Communication Services

Group communication is essential for multi-user applications. However, due to unpredictable node departures and non-deterministic network partitions, providing reliable and scalable group communication services is challenging when the applications are utilized by the users with heterogeneous capacities on a large scale. To address this challenge, we propose a novel replication scheme to achieve high reliability and low-cost scalability in group communication with following three features. First, it introduces a new concept of replication based on topological similarity, which empowers each node with an ability of measuring similarity between the nodes in topology. By eliminating the topological similarity between the replicas, it intelligently mitigates service interruptions caused by node failures and network partitions. Second, instead of specifying the number of replicas, it provides a technique for nodes to dynamically adapt the replication placement schemes by exploiting functionality importance of the nodes in the group- communication session. It eliminates the bottleneck problem and improves the network resource utilization. Third, the scheme is self-converging and it can stabilize within a few adaptations even facing a high churn rate. Extensive simulations show that it yields significant improvements in reduction of replication overhead and service interruption when comparing to existing approaches.